US Secretary of State Mike Pompeo held separate talks with King Salman and Crown Prince Mohammed bin Salman on Tuesday in Riyadh as the situation over missing journalist Jamal Khashoggi continues.

According to CNN, Pompeo had a short discussion with King Salman before a longer meeting with Crown Prince Mohammed bin Salman.

US State Department spokeswoman Heather Nauert said Pompeo “thanked the King for his commitment to supporting a thorough, transparent, and timely investigation” of the Khashoggi case and expressed “concern” about the case to the foreign minister, Adel Al-Jubeir.